Reduction of ITPA gene expression in human gastric adeno carcinoma tumors

A pure nucleotide pool is an essential precursor of correct DNA replication and prevention of mutagenesis and abnormality in a living cell. Inosine triphosphatase (ITPase) is a critical enzyme to remove any deaminated rough purine nucleotides such as inosine from nucleotide pool. It has been shown that the rate of substitution mutation in genomic DNA increase by abnormal function and expression of ITPA gene. The object of this study was comparisons the ITPA gene expression between human adenocarcinoma tumor with the normal margins tissues. the expression of ITPA gene was examined in 24 pairs of gastric adenocarcinoma tumor and their normal adjacent tissues using quantitative Real-Time PCR technique. the analysis gene expression showed reduction in tumor tissue in comparison with their adjacent normal tissues. The reduction in ITPA gene expression is especially significant in higher grade samples. with regard to the biological function of ITPA gene in omitting the rough deaminated purines from the nucleotides pool, it seems that lower expression of this gene can be considered as a risk factor for development and progression of gastric cancer. Also abnormality in this gene increase the frequency of mutation in genomic DNA and make a suitable background for higher genomic instability.